Semiconductor laser drive apparatus and image forming apparatus
a technology of semiconductor lasers and drive apparatuses, which is applied in semiconductor lasers, laser details, printing, etc., can solve the problems of excellent light-emission delay and inability to obtain light-emission pulse widths
Active Publication Date: 2015-09-08
RICOH KK
View PDF3 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
[0005]A semiconductor laser drive apparatus used in a high-speed, high-definition laser printer, digital copier, and the like, needs to drive a semiconductor laser element with a desired light-emission delay and light-emission pulse width. Hence, a technique is known in which a threshold current at which the semiconductor laser element emits light is detected in advance, and the threshold current is caused to flow through the semiconductor laser element as a bias current immediately before the semiconductor laser element emits light, to activate the semiconductor laser element. By this, light-emission delay is reduced, enabling to obtain an excellent light-emission pulse width at turn-on.
Problems solved by technology
In this case, there is a problem that an excellent light-emission delay and light-emission pulse width cannot be obtained.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0019]The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes” and / or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.
[0020]In describing example embodiments shown in the drawings, specific terminology is employed for the sake of clarity. However, the present disclosure is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that operate in a s...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
A semiconductor laser drive apparatus includes: a current setting circuit that stores a first set value for a light-emission current obtained by subtracting a first bias current used when the semiconductor laser element emits light, from a drive current used when the semiconductor laser element emits light, a second set value for the first bias current, and a third set value for a second bias current used when the semiconductor laser element does not emit light; a first current generator circuit that generates a first input current from the first set value; a second current generator circuit that generates a second input current from the second set value and a third input current from the third set value; and a switching circuit that supplies a sum of the first and second input currents to a drive circuit when a light-emission control signal is on, and the third input current to the drive circuit when the light-emission control signal is off.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This patent application is based on and claims priority pursuant to 35 U.S.C. §119 to Japanese Patent Application No. 2013-102677, filed on May 15, 2013, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.BACKGROUND[0002]1. Technical Field[0003]The present invention relates to a semiconductor laser drive apparatus and an image forming apparatus using the semiconductor laser drive apparatus.[0004]2. Background Art[0005]A semiconductor laser drive apparatus used in a high-speed, high-definition laser printer, digital copier, and the like, needs to drive a semiconductor laser element with a desired light-emission delay and light-emission pulse width. Hence, a technique is known in which a threshold current at which the semiconductor laser element emits light is detected in advance, and the threshold current is caused to flow through the semiconductor laser element as a bias current immediate...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & AuthorityPatents(United States)
IPC IPC(8): H01S5/0683H01S5/042H01S5/40
CPCH01S5/0683H01S5/042H01S5/4025B41J2/455
InventorSUMINO, DAIJIROWATANABE, TAKAO
OwnerRICOH KK